过氧化物酶体增殖物激活受体γC161T基因多态性与糖皮质激素性骨质疏松症的关系

目的 探讨中国人过氧化物酶体增殖物激活受体γ(PPARγ)基因外显子6 C161T多态性与糖皮质激素性骨质疏松症(GIO)的相关关系。方法 应用聚合酶链反应-限制性片段长度多态性(PCR-RELP)方法测定208例正常健康人（Ⅰ组）、168例非GIO患者（Ⅱ组）和104例GIO患者（Ⅲ组）PPARγ基因外显子6 C161T的基因型。应用双能X线骨密度仪(DEXA)测定股骨、腰椎等部位的骨密度。 结果 外显子6 C161T有CC、CT、TT 3种基因型。GIO组CC基因型频率显著低于正常对照组；CT和TT基因型频率显著高于正常对照组。非GIO组、应用激素组（GIO组＋非GIO组）与正常对照组比较，各基因型频率差异均无统计学意义。正常对照组C161T的CC基因型组各部位的骨密度有高于CT和TT基因型组的趋势，但差异无统计学意义。非GIO组和GIO组C161T的CC基因型组腰椎的骨密度明显高于CT和TT基因型组 (P ＜ 0.05)，分别为非GIO组CC型（1.04±0.17） g/cm2，CT+TT型（1.02±0.07） g/cm2；GIO组CC型（0.94±0.12） g/cm2，CT+TT型（0.83±0.08） g/cm2。经年龄、体重指数等因素校正后，差异仍有统计学意义(P ＜ 0.05）。 结论 PPARγ基因C161T基因型在正常人和应用激素患者之间无明显差异，它可能与肾小球肾炎的发病无关。C161T基因型在GIO组和正常对照组之间差异有统计学意义，它可能与糖皮质激素性骨质疏松症的发病有关。PPARγ基因C161T多态性与应用糖皮质激素患者腰椎的骨密度有关。等位基因C可能是骨量的保护因子，它可能与应用糖皮质激素后骨量的丢失有关。

Relationship between peroxisome proliferator-activated receptor γ gene C161T polymorphism and glucocorticoid-induced osteoporosis

Objective To evaluate the relationship of C161T polymorphism in peroxisome proliferator-activated receptor γ (PPARγ) gene with glucocorticoid -induced osteoporosis(GIO) in Chinese population. Methods The C161T genotypes of PPARγ exon 6 were determined by PCR-RFLP in 208 healthy persons(group Ⅰ), 168 patients without GIO(group Ⅱ) and 104 patients of GIO(group Ⅲ) . Bone mineral density(BMD) at lumbar spine, femoral neck， trochanter and Ward’s triangle were measured by dual-energy X-ray absorptiometry(DEXA). Results Hardy-Weinberg equilibrium was evident for PPARγ polymorphism. PPARγ gene CC genotype frequency was lower in group Ⅲ as compared with groupⅠ. CT and TT genotype frequencies were higher in group Ⅲ as compared with groupⅠ. CC, CT and TT genotype frequencies were not significantly different among group Ⅱ, group Ⅱ+Ⅲand groupⅠ. BMD of lumbar spine in group Ⅱand gronp Ⅲpatients with CC genotype was lower as compared to those with CT+TT (P ＜ 0.05). In groupⅡ, the BMD of CC and CT+TT genotypes at lumbar spine area was (1.04±0.17) g/cm2 and (1.02±0.07) g/cm2 respectively. In groupⅢ, the BMD at lumbar spine area was (0.94±0.12) g/cm2, (0.83±0.08) g/cm2 of CC, CT+TT genotypes respectively. The significant difference was also presented after adjusted by age and BMI. Conclusions The frequency of the genotype is not significantly different between groupⅠand groupⅡ+Ⅲ, which indicates that genotype may not be related with the onset of glomerulonephritis. The frequency of the genotype is significantly different between group Ⅰ and group Ⅲ, which indicates that genotype may be related with the onset. Polymorphism of C161T in PPARγ gene may have an effect on the BMD of lumbar spine of the patients receiving glucocorticoid group (Ⅱ+Ⅲ).Allele C may be a protection factor of bone mass.